A simple approach -force balance method (FBM) -has been proposed to calculate geometric correction factors in linear elastic fracture mechanics [1]. In the method, the stress distribution ahead of the crack tip along the crack-line for a finite-width plate has to be involved, which was postulated to be associated with the stress distribution for the corresponding infinite plate, modified by a geometric correction factor. The geometric correction factor can then be determined by means of equilibrium conditions of forces and torques along the crack-line.By virtue of the FBM, a number of geometric correction factors for finite-width center cracked specimens, subjected to different configurations of loading, have been deduced e.g. [1][2][3]. They were found to be in good agreement with those reported in the literature. However, the assumption regarding the stress distribution in front of the crack tip along the crack-line in a finite-width specimen is lacking in mathematical rigour. In order to verify the applicability of the obtained geometric correction factors, it is thus essential to evaluate this assumption for various loading configurations.In [4][5][6] the stress distributions ahead of the crack tip along the crack-line for the standard center cracked tension (CCT) specimen and a finite-width plate loaded by a pair of concentrated forces on the center line of the specimen have numerically been assessed by means of the finite element method (FEM). The assumed stress distributions were found to be in good accordance with the obtained numerical results, especially in the vicinity of the crack tip. In this paper the stress distribution ahead of the crack tip along the crack-line for the center cracked specimen, loaded by uniformly distributed stresses on the center portion of the crack (see Fig. 1) is numerically evaluated by means of FEM. Int Journ of Fracture 75 R4For the loading configuration depicted in Fig. 1, the stress distribution (.~) ahead of the crack tip along the crack-line for the finite width plate (width W) is assumed to bewhere the singular term of the Westergaard function [7] available for the corresponding infinite-width plate is modified by a geometric correction factor Y.In (1), 2a is the crack length, 2b is the acting region of stresses tJ, x is the distance from the center of the crack, as shown in Fig. 1. By means of FBM, the stress intensity factor K and geometric correction factor Y can be obtained as(2) y = "~W 2-4 a 2 sin-l(b/a) Analogous to the work in [4,5], a specimen of total height L=30 with a center crack of length a=l is considered. Hence, in the range of interest (i.e., 0.2<2a/W<0.8) the minimum ratio of L over W is 3, which is acceptable from a practical point of view. Due to the symmetry only a quarter of the specimen (i.e., the right-upper part) is discretized. A typical FE-mesh corresponding to 2a/W=0.2 is displayed in Fig. 2, consisting of 690 four-node bilinear elements and 761 nodes. In view of the singularity at the crack tip the FE-mesh close to this point is relatively...

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